This invention relates in general to bearings and more particularly to a roller bearing suitable for use on automotive axles and a wheel mounting that utilizes such a bearing.
Many subcompact automobiles of current manufacture are driven through their front wheels, and to accommodate this type drive, special wheel mountings have been developed. The typical wheel mounting of this type includes a steering knuckle that pivots to afford the front wheel motion that is necessary to steer the vehicle. The knuckle contains a double row angular contact ball bearing, the outer race of which is a single ring that is pressed into the steering knuckle and retained in place by snap rings that fit into grooves in the knuckle. The inner race of the bearing, on the other hand, consists of two rings--one for each row of balls--and these rings have a wheel hub or so-called drive flange passed through their bores. The powered front axle, in turn, fits through the hub, it being coupled with the hub by means of a spline. A wheel mounting of this construction is illustrated in U.S. Pat. No. 4,010,986.
Conventional wheel mountings of the foregoing construction are relatively easy to disassemble so that the bearings or other internal parts may be replaced. Basically, the steering knuckle is detached from its pivot joints and the entire wheel mounting is pulled off of the splined axle. Then the hub is pressed out of the inboard ring of the inner race. The outboard inner ring merely remains with the hub and passes out of the outboard ring of balls. In this regard, the cage that maintains the proper spacing between adjacent balls of the outboard row also retains the balls within the outer race once the hub has been withdrawn. At this point the snap rings are accessible and may be removed to free the outer race ring.
While the ball bearings of the typical front wheel drive wheel mounting are inexpensive to manufacture and lend themselves to easy disassembly of the mounting, they are not always suited for heavier vehicles, for these vehicles often require the durability of tapered roller bearings in their wheel mountings. Tapered roller bearings are manufactured in configurations that are easily substituted for the typical double row angular ball bearing, and in such configurations they comprise a double cup, a pair of cones that fit into the double cup from each of its ends and two rows of tapered rollers that fit the raceways on the cup and cones, with the large diameter ends of the rollers being presented outwardly. Each cone has ribs at both ends of its raceway, the one at the large end serving to accommodate the thrust forces that tend to expel the rollers from the bearing and the one at the small end serving to prevent the rollers from sliding off of that end of the cone when the cone is handled apart from its cup. The rib at the small end, however, prevents the mounting from being dismantled in the usual manner, for as the hub is pressed out of the steering knuckle, the rollers of the outboard row will, in effect, lodge between the retaining rib at the small end of the outboard cone and the snap ring at the outboard end of the double cup. This causes the force, that is transmitted through the rollers to shear off the snap ring, and render the snap ring extremely difficult to remove.